Line-Interactive UPSs
These
UPSs
are hybrid devices that offer a higher level of performance by
adding voltage regulation features to conventional standby designs.
They are most effective in protecting against average high-voltage
spikes and switching transients.
Typically, line-interactive UPSs switch to battery to adjust the tap
location down at certain intervals to maintain the output voltage as
the input voltage changes. When the unit reaches a pre-determined
point, it eventually goes to battery full-time. More advanced
line-interactive UPSs provide a level of voltage regulation without
engaging batteries and they deliver tighter output voltage windows
than their predecessors.
A unit that is able to deliver consistent, regulated output voltage
in a window of -10 percent to +6 percent meets (or exceeds) the
operational guidelines recommended by the Computer Business
Equipment Manufacturers Association. Switching to batteries on an
as-needed basis means that line-interactive UPSs are able to operate
more efficiently, but it necessitates that batteries be constantly
recharged in a timely manner. Recharging happens in one of two ways
– by using a standard trickle charge method or , in the case of
Powerware, a proprietary three-stage charging technique called ABMTM
(Advanced
Battery Management). Batteries that are constantly trickle charged
tend to reach the end of their useful life more quickly than those
using ABM. In addition to nearly doubling battery service life, ABM
optimizes recharge time and provides up to 60 days advanced
notification of pending battery failure.
Line-interactive UPSs are frequently used to
protect a variety of networking devices, from hubs
and routers to servers.
Line-Interactive UPSs
